Improvement in tubular cutting-punches



. Z Sheets-Sheet1. I. A. SMART. TUBULAR CUTTING PUNCHES. No. 174,386.Patented March 7,1876,

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2 Sheets-SheetZ. J, ALSMAR'IL. TUBULAR CUTTING PU-NCHES.

No.174,386; Patented Much 7,1876.

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WITNESSES. INVENTOR.

N4 FETUS, FHOTO-LITHOGRAPHEFL WASHlNGTON, D. C.

UNITED STATES PATENT DFFIGE.

, JASPER A.,SMART, or EAST MEDFORD, MASSACHUSETTS.

IMPROVEMENT IN TUBULAR CUT TlNG-PUN CHES.

Specification forming part of .Letters Patent No. 174,386, dated March7, 1876 application filed January 3, 1876.

.To all whom it may" concern Be it known that I, JASPER A. SMART, ofEast Medford, in the county of Middlesex and State of Massachusetts,have invented a new and useful Tubular Cutting-Punch and a method ofproducing the same,.of which the following, taken in connection with theaccompanying drawings, is a specification:

The object of my invention is the production, at a comparatively smallcost, of small tubular punches to be used in gangs or clusters, arranged according to some regular geometrical design, for the purpose ofperforating leather, cloth, paper, or other like material.

My invention relates, first, to the construction of the tubular punch;and it consists in striking up the tubular punch from a plate of iron orsteel by displacing the metalto form a taper hole through the plate, andforcing the metal so displaced outward from the side of the plate in theform of an annular projection, every part of the outer edge of which ise"qui distant from the surface of the plate from which it is formed. Itfurther consists in forming a series of tubular punches, arranged torepresent any desired design, in one piece,

' with a connecting-plate of which each of said punches forms anintegral part.

My invention relates, in the second place, to the tools or dies by whichsaid tubular punches are formed, and the method of applying them to forma tubular cutting-punch projecting from the side of a plate of metal, ofwhich it forms an integral part, by displacing a portion of the metal ofsaid plate, and forcing it out- 'ward from the side of said plate in theform of an annular projection; and it consists in the use, for thepurpose, of a female die, having a conical cavity formed therein of thedesired diameter andtaper to give the proper form and size to the punch,and a male die or punch havingits working end made to fit the interiorof the cavity in the female die, with its point slightly rounded, saiddies being firmly secured in proper position, with their axes in line,in a suitable press in such a manner that a suitable reciprocatingmotion may be imparted to the male die. It further consists in formingupon one side of the female die a longitudinal groove or channel, toserve,

tubular punch is determined.

I in conjunction with the first annular projection or tubular punchformed, as, a register or gage, by which the position of the next In thedrawings, Figure 1 is a plan of a punch-plate,havinga series of tubularpunches projecting therefrom arranged to form a suitable design forperforating a toe-cap for a boot or shoe. Fig. 2 is a section of thesame on line as w on Fig. 1. Fig. 3 is a side elevation, and Fig. 4 aplan, of the female die for forming the tubular punch. Fig. 5 is anelevation of the male die or solid punch, andFig. 6 isa section,illustrating the method of applying the .dies to form the tubular punch.Figs. -7 and 8 are plan and sectional views of a single tubular punch.

A is a plate of metal, which may be soft annealed steel, or bestcharcoal-iron, upon the upper side of which is marked, in any suitablemanner, the design which it is desirable to reproduce, by means of thegang-punch, in leather, cloth, or other flexible material. The plate Ais placed upon the end of the female die B, with one of the points inthe design directly beneath the point of the male punch 0, when,

by a suitable operation of the press in which the dies are mounted, themale punch is forced into the metal, perforating it, and, by virtue ofits conical form, forcing the metal displaced downward into the femaledie, as shown in Fig. 6. The metal thus displaced and thrown downward.forms an unbroken annular projection, 0, from the under side of theplate, somewhat smaller at its end than at its junction with the body oftheplate, and having a tapering hole through its center, extending tothe.

upper side of the plate, through whichthe core or piece of material cutout by the punch is delivered in a well-known manner. The female die Bis formed on the end of a steel rod, provided with screw-threads a, bymeans of which (and suitable nuts not shown) it is held in position inthe press, though it may be made of different form and be secured invarious ways to the bed of the press. 1 This die B has formed ip its enda simple tapering hole or recess, b, of suitable form, and havingstraight sides, as clearly shown in Fig. 6, and has also formed upon oneside of its exterior a groove, d, extending longitudinally of thedie-rod B, as shown in Figs. 3 and 4.

- by an excess of metal 'upon each side of the groove, which serves as abrace to support the walls of the die against separation.

The male die or punch O is made from a rod of steel, having its workingend tapered to a nearly sharp point to correspond to the form of therecess b in the female die. Theplates A-after the tubular projections care all formed, and their ends brought to aneven height from the surfaceof the plate by a file, or rubbing upon a flat level surfacesuppliedwith a suitable abrading material, andthe burr removed from theouter corner of each punch by means of ahollow or outside reamer-- aretempered, if made of steel, or case-hardened, if made of iron.

What I claim as new, and desire to secure by Letters Patent of theUnited States, is-

1. As a new article of manufacture, a tubular cutting-punch formed byperforating a plate of metal and forcing the metal displaced in the actof perforation outward in the form of an annular ring, having anunbroken cut-' ting-edge equidistant from the plate to which it isattached, and of which it forms an integralpart, substantially asdescribed.

2. A series or gang of tubular cuttingpunches struck up from and formingan integral part of a single plate of sheet metal, and arranged torepresent any desired sym m etric'al or, ornamental design, and. adaptedto transfer said design to leather, cloth, or other like material byperforating the same, substantially as described.

3. The method of forming tubular cutting punches from a plate of metalto which they are attached, and of which they-form an integral part,after being formed, by subjecting said plate of metal to the action of aconicalpointed punch or male die, and a female die provided with acorresponding conical recess, substantially as described.

4. The female die B, provided with the conical recess or mold b andexterior longitudinal groove d, adapted for use as and 'for the purposedescribed. I

5. The combination of the conicalrpointed punch U and the female die B,provided with the corresponding conical recess 1), as a means of formingconical annularprojections from the side of a thin plate of metal, asand for the purposes described.

Executed at Boston, Massachusetts, this 31st day of December, 1875.

JASPER A. SMART.

Witnesses:

WM. P. EDWARDS, E. A. HEMMENWAY'.

